1. Field of the Invention
This invention relates generally to the monitoring of a plurality of analog signals and, more particularly, to the periodic processing of the monitored signals.
2. Description of the Related Art
As more complex automotive and process systems have evolved, the monitoring and control functions have become more complex. Typically, peripheral systems, such as sensor elements, provide status and parameter signals to a processing unit. Based on the status and parameter signals, a processing unit can provide control signals to insure that the status and parameter signals are constrained within acceptable values.
These control systems can elaborate, including whole subsystems that can automatically respond to a situation that requires response. Such a dedicated system can typically be expensive and inflexible. Moreover, the requirements for the status and parameter monitoring can be diverse. The processing unit may need to see every status and parameter signal group, or can review the status of the apparatus only periodically.
The status and parameters signals are frequently analog signals, a format generally incompatible with the requirements of a processing unit. While it would possible to provide each signal source with an analog-to-digital converter, such a system would be too expensive in many applications. More typically, the analog signal groups from a plurality of sources are applied to a single analog-to-digital converter and various techniques then employed to provide the signal groups required by the processing unit to generate timely control signals.
A need has been felt for apparatus and an associated method for providing an improved technique for processing incoming analog signals. It would be a more particular feature of the apparatus and associated method to reduce the chance of identifying an overflow error in the buffer registers of an analog-to-digital converter unit. It would be yet another feature of the apparatus and associated method for provide an analog-to-digital converter unit that can be used efficiently when incoming analog signals need be examined only periodically. It would be still another feature of the apparatus and associated method to provide an analog-to-digital converter unit that can provide for continuous monitoring of a plurality of analog signals or can provide periodic monitoring of a plurality of analog signals. It would be a still further feature of the apparatus and associated method to be able to retrieve converted signals directly from the analog-to-digital register bank. It would be a still further feature of the apparatus and associated method to retrieve the converted signal groups in the in the analog-to-digital converter unit without involving the control unit of the analog-to-digital converter unit.